Spetroscopic monitoring of active galactic nuclei from CTIO. II. IC 4329A, ESO 141-G55, Arakelian 120, and Fairall 9

Abstract

The results of an intensive monitoring campaign on the Seyfert 1 galaxies IC 4329A and ESO 141-G55 are presented. Variability was detected in both continuum and broad e issjon line fluxes, and the cross-correlation analysis indicates that the most likely delay between the vanahons of the 6225 Å continuum and the response of the Hβ and Hα emission lines for IC 4329A is ~15-25 days. For ESO 141-G55, the time-series analysis was inconclusive, and we could not obtain a clear cross-correlation signal between the lines and continuum light curves. We also present new data obtamefor AKN 120 and Fairall 9, consisting of two sets of optical spectra taken ~4 months apart. Both objects underwent not only significant flux variability (by up to a factor of ~2) in this interval but also strong Hα and Hβ profile variations.